Albumin from human plasma serum has broad application in the field of medicine. For this reason, there is a high demand for high purity albumin, i.e., on the order of at least 97% pure. Besides the isolation of albumin by cold ethanol precipitation, use of chromatographic treatment processes has received some attention. See, for example, Curling, "Albumin Purification by Ion Exchange Chromatography", pages 77 to 91, in Methods of Plasma Protein Fractionation, Academic Press, London (1980). In such protein chromatography separation methods, the separation capacity of the conventional particulate adsorber materials generally used is limited by pore-diffusion effects. Chromatographic processes using membrane adsorbers, on the other hand, by virtue of their microporous structure, permit substantially greater transfer of the proteins to the adsorbing sites within the membrane adsorber, thereby allowing an increased separation capacity.
Lacoste-Bourgeacq et al., in 32 Chromatographia 27 (1991), describe the chromatographic separation of albumin from fraction IV of the Kistler and Nitschmann fractionation of blood plasma on weakly basic and strongly acidic membrane adsorbers. A drawback to this known process is that the albumin fraction, following its elution from the weakly basic membrane adsorber, must undergo a separate treatment step before it can be fed to the strongly acid membrane adsorber. Not surprisingly, the process is very inefficient in that albumin is obtained in a relatively low yield and purity of 66% and 90%, respectively.
There is therefore still a need in the art of albumin recovery for a simple method leading to high yields and purity.